A DERIVATION OF MATRIC POTENTIAL IN FROZEN SOIL 

Masaru MIZOGUCHI

Faculty of Bioresources, Mie University, Tsu, Mie 514, Japan 

Abstract 

Matric potential in frozen soil is derived from equilibrium between 
unfrozen water and ice in frozen saline soil. The matric potential in 
frozen soil, expressed here in pressure unit, is approximately 
expressed as a linear function of temperature, ice pressure and 
osmotic pressure, of which coefficients are 1,23 (MPa/'C) , l.1 and 
l.O, respectively. The direction of water movement is determined by
 a sign of the difference in the sum of matric plus gravitational 
potentials between frozen and unfrozen regions. It is predicted 
from the derived equation that heaving pressure is proportional to 
freezing temperature and decreases with increasing solute 
concentration. 

Key words: 
Matric potential, Unfrozen water,Temperature , Solute , Heaving 
pressure